Combustion deposition systems and methods of use

ABSTRACT

Combustion deposition systems and methods of using combustion deposition systems are disclosed. In an embodiment, a combustion deposition system may include a burner that is in fluid communication with at least one supply of at least one precursor such that the at least one precursor can be introduced to a flame output from the burner, at least one electrode positioned at least proximate to the flame, and a voltage source operably coupled to the at least one electrode. The at least one electrode and the at least one voltage source may be configured to generate an electric field for influencing at least one of flame shape, flame temperature, or kinetics of chemical reactions occurring within the flame, thereby providing enhanced selective control of combustion deposition characteristics. For example, the combustion deposition systems disclosed herein may, for example, be configured to control deposition of a combustion-deposited film on a substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No. 61/805,203 filed on 26 Mar. 2013, the disclosure of which is incorporated herein, in its entirety, by this reference.

BACKGROUND

Combustion flames at atmospheric pressure have been used to deposit a variety of materials, such as metal oxides, glasses, and ceramics. The technique is commonly referred to as combustion chemical vapor deposition (“CCVD”) and offers an economical route for surface deposition. For example, diamond can be deposited via CCVD from an acetylene-oxygen flame. Other examples of materials that can be deposited via CCVD include oxidation of silane flames to form silica and silicates.

Most applications of CCVD are for coating a workpiece with a functional coating, such as an oxide layer on a metal surface. Other applications use the substrate as a deposition mandrel that is subsequently liberated from the deposit, such as the production of free standing diamonds. In most CCVD reaction configurations, a premixed flame of reactants is directed towards a cooled substrate to deposit a combustion-deposited material on the cooled substrate resulting from interaction of the reactants with the flame.

SUMMARY

Embodiments disclosed herein relate to combustion deposition systems and methods of using such combustion deposition systems. The combustion deposition systems disclosed herein may be configured to selectively electrodynamically influence at least one characteristic of combustion in a flame and/or at least one characteristic of a combustion-deposited material.

In an embodiment, a combustion deposition system is disclosed. The combustion deposition system includes a burner configured to output a flame, and at least one supply of at least one precursor in fluid communication with the burner such that the at least one precursor can be introduced to the flame. The at least one precursor is for forming a combustion-deposited material by interacting with the flame. The combustion deposition system may further include at least one electrode positioned at least proximate to the flame when the flame is output from the burner, and at least one voltage source operatively coupled to the at least one electrode. The at least one electrode and the at least one voltage source are collectively configured to generate an electric field in one or more regions at least proximate to the flame. The electric field may be effective to influence at least one characteristic of combustion of the at least one precursor in the flame and/or at least one characteristic of the combustion-deposited material.

In an embodiment, a method of combustion flame deposition is disclosed. The method includes directing a flame output from a burner toward a substrate, and introducing at least one precursor into the flame. The at least one precursor is for forming a combustion-deposited material to be deposited on the substrate by interacting with the flame. The method further includes applying an electric field at least proximate to the flame to selectively influence at least one characteristic of combustion in the flame and/or at least one characteristic of the combustion-deposited material. The method also includes combustion depositing the combustion-deposited material onto the substrate from the at least one precursor introduced to the flame.

By choosing suitable precursor material(s), the combustion deposition systems and methods described herein may be used to deposit films, particles, or material layers that include metals, alloys, metal oxides, nitrides, diamond, diamond-like carbon, carbides, fluorides, borides, carbonates, or combinations thereof.

Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a combustion deposition system including a substrate positioning table and a substrate cooling/heating stage according to an embodiment.

FIG. 2 is an isometric view of a combustion deposition system including a flame nozzle that serves as an electrode according to an embodiment, with a substrate and a combustion-deposited film shown in cross-section.

FIG. 3 is an isometric view of a combustion deposition system including a conductive substrate that serves as one electrode and a flame nozzle that serves as a second electrode according to an embodiment, with a substrate and a combustion-deposited film shown in cross-section.

FIG. 4 is an isometric view of a combustion deposition system including an electrode assembly having a plurality of electrodes according to an embodiment.

FIG. 5 is an isometric view of a combustion deposition system according to an embodiment, with a substrate and a combustion-deposited film along with multiple electrodes shown in cross-section.

FIG. 6 is an isometric view of a combustion deposition system including a plurality of electrodes arranged in a generally hollow three-dimensional configuration for laterally surrounding a flame according to another embodiment.

FIG. 7 is an isometric view of a combustion deposition system including at least one sharp electrode positioned adjacent to a flame according to another embodiment, with a substrate and a combustion-deposited film along with electrodes shown in cross-section.

FIG. 8 is an isometric view of a combustion deposition system including ionizing elements positioned adjacent to the flame according to another embodiment with a substrate and a combustion-deposited film along with electrodes shown in cross-section.

DETAILED DESCRIPTION

Embodiments disclosed herein relate to combustion deposition systems (e.g., CCVD systems) and methods of using such combustion deposition systems for depositing a material, such as a film or particles. For example, the combustion deposition systems disclosed herein may be configured to control one or more of flame shape, flame temperature, or kinetics of chemical reactions occurring within the flame via an applied electric field, thereby providing selective control of combustion deposition characteristics of the flame and/or selective control of one or more characteristics of a combustion-deposited material. The combustion-deposited material may be, for example, used as hard facing on a substrate for wear applications, as diamond thin films, to manufacture diamond crystals, oxide coatings for transparent electrical conductors or semiconductors, electrical insulator coatings, optical coatings, and many other applications, without limitation.

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the disclosure.

FIG. 1 is an isometric view of a combustion deposition system 100 according to an embodiment. The combustion deposition system 100 includes at least one burner 106 that includes at least one nozzle 102 configured to output a flame 104. The burner 106 may be in fluid communication with at least one supply of at least one precursor 108 so that the at least one forming precursor 108 can be introduced to the flame 104. The at least one precursor may be introduced through a passageway in the burner 106 or flowed from a location adjacent to the nozzle 102 and into the flame 104. The at least one precursor 108 may be one or more suitable gases for producing a combustion-deposited film 116 or other material on a substrate 118 when combusted by the flame 104. For example, the at least one precursor 108 may be at least one of a metal-organic compound gas, a metal salt gas, or a metal-salt solution that is introduced to the flame 104. The flame 104 is moved closely above or contacting the surface of the substrate 118 to be coated. The high energy within the flame 104 may convert the at least one precursor into highly reactive intermediates, which may readily react with the substrate 118, thereby forming a firmly adhering deposit, such as the combustion-deposited film 116 or other material, such as discrete particles (e.g., discrete nanoparticles). The flame deposition of the combustion-deposited film 116 is typically conducted at atmospheric pressure, although other pressure conditions may be employed.

The combustion deposition system 100 further includes at least one electrode 110 that may be positioned at least proximate to the flame 104 when the flame 104 is output from the nozzle 102. A voltage source 112 is operatively coupled to the at least one electrode 110. The at least one electrode 110 and the voltage source 112 may be collectively configured to apply an electric field to one or more regions 114 at least proximate to the flame 104 (e.g., adjacent to and/or in the flame 104). In the illustrated embodiment, the at least one electrode 110 is shown as being separate and distinct from the nozzle 102 and the burner 106. However, in other embodiments (e.g., FIG. 2), the nozzle 102 and/or the burner 106 may act as an electrode as an alternative to or in addition to the at least one electrode 110.

The voltage applied to the at least one electrode 110 by the voltage source 112 may be a substantially constant DC voltage, a time-varying voltage, or a DC voltage with a superimposed time-varying voltage, without limitation. For example, in an embodiment, the voltage source 112 may be configured to apply a substantially constant voltage or time-varying voltage to the at least one electrode 110 to generate a corresponding substantially constant or time-varying electric field. A time-varying voltage may, for example, have a periodic voltage waveform with a frequency in a range from about 50 Hz to 10,000 Hz, such as 200 Hz to 800 Hz. The waveform of a time-varying voltage may be a square waveform, a sine waveform, a triangular waveform, a saw tooth waveform, or another suitable waveform. The amplitude of the time-varying voltage may, for example, be in a range of about +/−1000 volts to about +/−115,000, such as about +/−8000 volts to about +/−40,000 volts.

The application of the electric field to the one or more regions 114 at least proximate to the flame 104 may, for example, enable controlling the resultant properties of the combustion-deposited film 116. The electric field may be at least partially controlled to manipulate movement of electrically charged molecules (ions) that are a product of the combustion process. For example, the controlled electric field may create electrostatic forces (e.g., Coulombic body forces) within a gas cloud of the flame 104 that may be manipulated to control flame shape, combustion chemistry, heat transfer through or away from a surface, or combinations thereof, as desired. Generally, by controlling a time, a direction, a strength, a location, a wave form, a frequency spectrum of the applied electric field, or combinations thereof, the applied electric field may influence one or more of combustion characteristics of the flame 104, a flame shape of the flame 104, heat transfer from the flame 104, or other characteristic in order to control and influence one or more characteristics of the combustion-deposited film 116, such as grain size of the combustion-deposited film 116, types of material phase(s) present in the combustion-deposited film 116, crystal structure of the combustion-deposited film 116, phase size of the one or more phases present in the combustion-deposited film 116, residual stresses in the combustion-deposited film 116, surface roughness of the combustion-deposited film 116, composition of the combustion-deposited film 116, thickness of the combustion-deposited film 116, reaction kinetics of the at least one precursor 108 within the flame 104, combinations thereof, or other combustion-deposited material properties.

As an example, control of the reaction kinetics of the at least one precursor 108 within the flame 104 may enable selective control of one or more characteristics of the combustion-deposited film 116 deposited onto a surface of the substrate 118. For example, the stoichiometric concentrations of the at least one precursor 108 may be manipulated and controlled by the application of the electric field to the one or more regions 114 at least proximate to the flame 104. Control of the stoichiometric concentrations may be used to provide further control of characteristics of the combustion-deposited film 116. For example, control of the stoichiometric concentrations may enable control of a growing crystal structure (not shown) on the surface of the substrate 118, the phase(s) in the combustion-deposited film 116, particle size of particle(s) (e.g., nanoparticles) deposited onto the surface of the substrate 118, surface roughness of the combustion-deposited film 116, residual stresses in the combustion-deposited film 116, combinations of the foregoing, or a number of other different resultant measurable physical properties of the combustion-deposited film 116.

In an embodiment, the at least one electrode 110 and the voltage source 112 may be collectively configured to influence the shape of an inner flame 128 of the flame 104 by varying the application of the electric field at selected times. For example, application of an electrical field in or near the region of the inner flame 128 may cause the flame to spread or flatten out, which may increase the surface area of the substrate 118 that may be covered by the flame 104. In an embodiment, the at least one electrode 110 and the voltage source 112 may be collectively configured to influence one or more kinetic properties of one or more chemical reactions within the flame 104. In an embodiment, the at least one electrode 110 and the voltage source 112 may be collectively configured to influence a stoichiometry of one or more chemical reactions within the flame 104. In an embodiment, the at least one electrode 110 and the voltage source 112 may be collectively configured to influence distribution of chemical species of the flame 104 by varying application of the electric field at selected locations and/or times in or near the flame 104. In an embodiment, the at least one electrode 110 and the voltage source 112 may be collectively configured to influence one or more combustion characteristics of the flame 104 by varying a voltage applied by the voltage source 112 at selected locations and/or times. In another embodiment, the voltage source 112 may be configured to change a polarity of the voltage applied to the electrode 110. In an embodiment, the voltage source 112 may be configured to vary a magnitude or frequency of a voltage applied by the voltage source 112 to the at least one electrode 110 at selected times and/or locations.

In the illustrated embodiment shown in FIG. 1, the combustion deposition system 100 may further include a cooling/heating stage 120 on which the substrate 118 may be positioned and a positioning table 122 configured to position the cooling/heating stage 120 and the substrate 118. However, in other embodiments, the cooling/heating stage 120 may be omitted. The cooling/heating stage 120 may be operatively coupled to the positioning table 122 and configured to provide temperature control of the substrate 118. The positioning table 122 is configured to position the substrate 118 in substantial contact with or near the flame 104, and/or at a selective distance 124 from the substrate 118 relative to an inner flame tip 126 of the inner flame 128 of the flame 104.

In an embodiment, the at least one supply of at least one precursor 108 may include one or more independent supplies of gases, such as ethylene, oxygen, acetylene, methane, tungsten hexafluoride, silane, or combinations thereof. For example, for deposition of diamond crystals onto a surface of a substrate, the at least one precursor 108 may include acetylene, oxygen, and ethylene. In another example, for deposition of silicate crystals onto a surface of a silica substrate, the at least one precursor 108 may include silane. Other precursors for the at least one precursor may include solutions injected into the flame 104, such as metal-salt solutions which may be ionically or covalently bound metal-salt solutions. Examples of suitable metal-salt solutions include silicon chloride, titanium chloride, tin chloride, or combinations thereof, which may be injected into the flame 104 and/or flame reaction to produce coatings of silica, titania, and tin oxide, respectively. The substrate 118 used within the system 100 may include at least one of silica, a silicate, diamond, molybdenum, glass, tungsten carbide, another type of carbide, or a metal and/or alloy that readily forms a carbide.

In an embodiment, the distance 124 from the inner flame tip 126 to the substrate 118 may be manipulated to facilitate control of the temperature of the flame 104 and the chemical species within the flame 104. The positioning table 122 may provide for control of the distance 124 between the substrate 118 and the flame 104. As illustrated in FIG. 1, the positioning table 122 may provide a motorized X-Y-Z stage to facilitate control of the distance 124 between the inner flame tip 124 and the substrate 118. For example the distance 124 between the inner flame tip 124 and the substrate 118 may be about 0.1 mm to about 2.0 mm, about 0.25 to about 1.5 mm, or about 0.25 mm to about 0.75 mm.

As discussed above, the temperature of the substrate 118 may be controlled by the cooling/heating stage 120. For example, the cooling/heating stage 120 may be configured to cool or heat the substrate 118 to about 700° C. to about 1050° C., about 700° C. to about 850° C., about 740° C. to about 900° C., about 740° C. to about 800° C., or about 760° C. to about 780° C. Such substrate cooling or heating may also alter the temperature of the flame 104, its combustive precursor(s) 108, and the resulting characteristics of the combustion-deposited film 116. For example, cooling the substrate 118 sufficiently may result in a generally smaller average deposition grain size of the combustion-deposited film 116 than an average deposition grain size of the film combustion product 116 without cooling the substrate 118. In another embodiment, cooling the substrate 118 sufficiently may result in a generally larger average deposition grain size of the combustion-deposited film 116 than an average deposition grain size of the combustion-deposited film 116 without cooling the substrate 118.

In an embodiment, the substrate 118 may be pretreated prior to the positioning of the substrate 118 onto the cooling/heating stage 120 and introducing the at least one precursor 108 into the flame 104. For example, a surface of the substrate 118 may be pre-seeded with one or more seed particles to promote nucleation and growth of the combustion-deposited film 116 and/or to assist and control characteristics of the deposition of the combustion-deposited film 116. In an embodiment, the one or more seed particles may be at least one of one of diamond particles, carbide particles, metal particles, alloy particles, metalloid particles, oxide particles, nitride particles, boride particles, carbonate particles, or the like. For example, to enhance the nucleation of diamond nucleation sites, the substrate 118 may be pre-seeded with diamond crystals having an average crystal size of about 0.10 μm to about 0.50 μm, or about 0.20 μm to about 0.30 μm. In another embodiment, the surface of the substrate 118 onto which the combustion-deposited film 116 is formed may be polished prior to introducing the at least one precursor into the flame 104. In another embodiment, the substrate 118 may be pretreated by scratching with diamond lapping paste prior to introducing the at least one precursor 108 into the flame 104.

FIGS. 2-8 illustrate various other embodiments of combustion control systems that are also configured to selective control combustion deposition characteristics of a flame and/or selective control of one or more characteristics of a combustion-deposited film or other material. The embodiments shown in FIGS. 2-8 may be used to control any one or combination of the characteristics of the flame and/or combustion-deposited material characteristics discussed above in relation to FIG. 1.

FIG. 2 is an isometric view of a combustion deposition system 200 including at least one burner 206 having at least one flame nozzle 202 configured to output a flame 204. The combustion deposition system 200 includes a voltage source 212 that is operatively coupled to the burner 206 such that the burner 206 may function as an electrode. For example, the nozzle 202 may be configured to act as the electrode for applying a controlled electric field to the flame 204 for controlling any one or combination of characteristics of the flame 204 and/or characteristics of a combustion-deposited film 208 or other material deposited onto a surface of a substrate 210, as disclosed herein. The voltage source 212 is configured to apply a controlled electric field at least proximate to the flame 204 via the nozzle 202 to control any one or combination of the characteristics of the flame and/or combustion-deposited material characteristics discussed above in relation to FIG. 1.

In another embodiment shown in FIG. 3, a combustion deposition system 300 includes at least one burner 306 having at least one flame nozzle 302 configured to output a flame 304, and a voltage source 312. The voltage source 312 is operatively coupled to the burner 306 and the substrate 310 such that at least one of the burner 306 or the substrate 310 may be biased by the voltage source 312 to generate an electrical field that influences deposition of a combustion-deposited film 308 or other material onto a substrate 310. For example, the substrate 310 may be electrically conductive, such as a metallic substrate or semiconducting substrate. For example, the metallic substrate may comprise steel or other metal or alloy and the semiconducting substrate may comprise silicon (e.g., polycrystalline or single-crystal silicon).

FIG. 4 is an isometric view of another embodiment of a combustion deposition system 400 that includes an electrode assembly 414 having a plurality of electrodes 416 formed on and bonded to a substrate 418. The combustion deposition system 400 includes at least one burner 406, at least one flame nozzle 402, and a voltage source 412. The voltage source 412 may be operatively coupled to the burner 406 which functions as an electrode and the electrode assembly 414 that includes the plurality of electrodes 416. However, in another embodiment, the voltage source 412 may be coupled to ground instead of the burner 406. In an embodiment, the voltage source 412 may be independently coupled to each or groups of the electrodes 416. The electrode assembly 414 may be configured to be mounted proximate to or in contact with a flame 404 for applying a controlled electric field to one or more regions at least proximate (e.g., adjacent) to the flame 404 for controlling one or more characteristics of the flame 404 in order to affect deposition of a combustion-deposited film 408 or other material onto a substrate 410. Each or some of the electrodes 414 may be electrically isolated from each other or electrically connected to each other. The voltage source 412 is configured to apply a controlled electric field at least proximate to the flame 404 via the electrode assembly 414 to control any one or combination of the characteristics of the flame and/or combustion-deposited material characteristics discussed above in relation to FIG. 1.

In the illustrated embodiment, each of the electrodes 416 is formed in a generally strip or bar-like geometry. However, in other embodiments, the electrodes 416 may be formed in a variety of different geometries. Moreover, while twelve electrodes are shown, in other embodiments, the electrode assembly 414 may include one, two, three, six, ten, or any other suitable number of electrodes. Additionally, while the electrode assembly 414 is shown including only a single row of the electrodes 416, in other embodiments, the electrodes 416 may be arranged in one or more different patterns. For example, the electrodes 416 may be arranged in two rows, three rows, five rows, or any other suitable number of rows. In other embodiments, the electrodes 416 may be arranged in a generally circular pattern, a generally spiraling pattern, a generally rectilinear pattern, along one or more linear paths, along one or more arcuate paths, combinations thereof, or in any other suitable pattern or arrangement. Such configurations may help the electrodes 402 and 414 control the characteristics of the flame 404 at different locations and/or times during the combustion process.

The substrate 418 of the electrode assembly 414 may be configured to support the electrodes 416. The substrate 418 may include a generally flat planar first surface, an opposing generally flat planar second surface, and a plurality of generally planar sides forming a periphery of the substrate 418. The electrodes 416 may be selectively formed on one or more portions of the first surface of the substrate 418. The substrate 418 may exhibit any desired sized and geometric shape suitable for supporting the electrodes 416 for a particular combustion application. For example, the substrate 418 may exhibit a rectangular-like configuration. In other embodiments, the substrate 418 may exhibit a generally elliptical configuration, a generally cross-like configuration, a generally triangular configuration, a generally annular configuration, a generally T-like configuration, a generally diamond-like configuration, combinations thereof, or any other suitable configuration. While the first and second surfaces of the substrate 418 are shown being generally planar, in other embodiments, one or more portions of the surface of the substrate 418 may be generally curved, contoured, planar, combinations thereof, or other suitable geometry. The substrate 418 may be generally rigid, semi-rigid, semi-flexible, or flexible. Additional embodiments of electrode assemblies are disclosed in U.S. Provisional Application No. 61/737,033 and U.S. patent application Ser. No. 14/104,612, and may be employed for the electrode assembly 414. U.S. Provisional Application No. 61/737,033 U.S. patent application Ser. No. 14/104,612 are each incorporated herein, in its entirety, by this reference.

FIG. 5 illustrates a combustion deposition system 500 according to another embodiment. The combustion deposition system 500 includes at least one burner 506, at least one flame nozzle 502 configured to output a flame 504, a voltage source 512, and a first electrode 514 spaced from a second electrode 516. For example, the first and second electrodes 514 and 516 may each be generally planar. However, in another embodiment, the first and second electrodes 514 and 516 may be unitary such as a cylindrical body that extends about the flame 504. The voltage source 512 may be operatively coupled to the burner 506 which functions as an electrode, the first electrode 514, and the second electrode 516. However, in another embodiment, the burner 506 may not be coupled to the voltage source 512. The electrodes 514, and 516 may be configured to be mounted proximate to or in contact with the flame 504 for applying a controlled electric field to one or more regions at least proximate to (e.g., adjacent) to the flame 504 for controlling one or more characteristics of the flame 504 and affecting deposition of a combustion-deposited film 508 onto a substrate 510. For example, the burner 506, and electrodes 514, and 516 may be configured to control one or more characteristics of the flame 504, such as, but not limited to, flame shape, flame, temperature, flame chemistry, precursor temperature, etc., or any other characteristic disclosed herein in order to alter/control how the combustion-deposited film 508 or other material is combustion deposited on the substrate 510. The voltage source 512 is configured to apply a controlled electric field via at least proximate to the flame 504 via the electrodes 506, 514, and 516 to control any one or combination of the characteristics of the flame and/or combustion-deposited material characteristics discussed above in relation to FIG. 1.

FIG. 6 is an isometric view of a combustion deposition system 600 that includes an electrode assembly 614 that includes a plurality of electrodes 616 arranged in a generally hollow three-dimensional configuration at least partially laterally surrounding a flame 604 according to another embodiment. The combustion deposition system 600 includes at least one burner 606, at least one flame nozzle 602 configured to output the flame 604, a voltage source 612, and an electrode assembly 614 that at least partially surrounds the burner 606 and at least a portion of the flame 604. For example, the electrode assembly 614 may laterally surround the flame 604.

The electrode assembly 614 may include a plurality of substrates 618 positioned and configured to form the hollow three-dimensional structure. Each of the substrates 618 includes rows of electrodes 616 formed thereon defining a corresponding electrode sub-assembly 615. In the illustrated embodiment, the electrode sub-assemblies 615 are positioned and configured to form a hollow generally hexagonal structure, with the electrodes 616 oriented on an interior of the hollow structure. In other embodiments, the electrode assembly 614 may define other hollow structures, such as a box-like structure, a generally diamond-like structure, a generally triangular structure, or any other suitable three-dimensional structure. Such hollow configurations may help the electrode assembly 614 influence combustion characteristics of the flame 604 about which the electrode assembly 614 extends by enabling the electrode assembly 614 to apply an electric field to the flame in substantially 360° about the flame. While six of the electrode sub-assemblies 615 of the electrode assembly 614 are shown in FIG. 6, in other embodiments, the electrode assembly 614 may include two, three, four, five, seven, eight, nine, ten, eleven, twelve, or any other suitable number of the electrode sub-assemblies 615. Additional embodiments of electrode assemblies are disclosed in U.S. Provisional Application No. 61/737,033 and may be employed for the electrode assembly 614.

In the embodiment illustrated in FIG. 6, the voltage source 612 may be operatively coupled to the burner 606 and the electrodes 616. The burner 606 and electrodes 616 may be configured to be mounted proximate to or in contact with a flame 604 for applying a controlled electric field to one or more regions at least proximate (e.g., adjacent) to the flame 604 for controlling one or more characteristics of the flame 604 in order to alter/control how a combustion-deposited film 608 or other material is deposited on a substrate 610. The voltage source 612 is configured to apply a controlled electric field via at least proximate to the flame 604 via the electrodes 616 to control any one or combination of the characteristics of the flame and/or combustion-deposited material characteristics discussed above in relation to FIG. 1.

In an embodiment, the voltage source 612 may be independently coupled to each or groups of the electrodes 616. In another embodiment, the voltage source 612 is not coupled to the burner 606.

Referring now to FIG. 7, a combustion deposition system 700 is shown, which includes an ionizing element 720 positioned adjacent to the flame 704 according to another embodiment. The combustion deposition system 700 includes at least one burner 706, at least one flame nozzle 702 configured to output a flame, and a voltage source 712. The voltage source 712 may be operatively coupled to the burner 706 and the ionizing element 720. The combustion deposition system 700 is configured to control one or more characteristics of the flame in order to control one or more characteristics of flame deposition of a combustion-deposited film 708 or other material on a substrate 710.

In an embodiment, the ionizing element 720 is a sharp electrode that is capable of streaming ions off therefrom into the flame 704. The ionizing element may be characterized as an ionizing electrode because the curvature and the increase of the electric field in the region proximate to the sharp tip 722 causes the ionizing element to eject ions upon application of a high electric field to the electrode 720.

The electric field in the vicinity of the tip 722 of the ionizing element 720 and/or charged particles (i.e., ions) emitted by the ionizing element may be affect motion of particles and/or chemical species (e.g., molecules) in the flame 704. One such effect may be to cause increased mixing of fuel and oxidizer and/or fuel and precursor elements within the flame 704. Increased mixing within the flame 704 may produce several effects on the flame 704, which may occur singly or in combination. For example, increased mixing within the flame 704 may increase or decrease the temperature of the flame 704, decrease pollutants (e.g., CO, NO_(x), soot, etc.), increase stability of the flame 704, change the shape of the flame, or decrease the chance of a flame blow out. Any of the foregoing changes in flame characteristics may affect the resultant properties of a combustion-deposited film 708 or other material deposited on a substrate 710.

The voltage applied to the ionizing element 720 by the voltage source 712 may be a substantially constant DC voltage, a time-varying voltage, or a DC voltage with a superimposed time-varying voltage. A time-varying voltage may, for example, have a periodic voltage waveform with a frequency in a range from about 50 Hz to 10,000 Hz, such as 200 Hz to 800 Hz. The waveform of a time-varying voltage may be a square waveform, a sine waveform, a triangular waveform, a saw tooth waveform, or another known waveform. The amplitude of the time-varying voltage may, for example, be in a range of about +/−1000 volts to about +/−115,000, e.g., about +/−8000 volts to about +/−40,000 volts.

FIG. 8 illustrates a combustion deposition system 800 that includes a plurality of ionizing elements 816 positioned adjacent to the flame 804 according to another embodiment. The combustion deposition system 800 includes at least one burner 806, at least one flame nozzle 802 configured to output a flame, and a voltage source 812. The voltage source 812 may be operatively coupled to the burner 806 and the plurality of ionizing elements 816. The combustion deposition system 800 is configured to control one or more characteristics of the flame 804 in order to control one or more characteristics of flame deposition of a combustion-deposited film 808 or other material on a substrate 810.

In the illustrated embodiment, the plurality of ionizing elements 816 are formed as sharp projections on a plate electrode 814, such as a portion of a metallic saw blade. As discussed above with respect to FIG. 7, the plurality of ionizing elements 816 may be configured as sharp electrodes that may be charged with a high voltage so as to eject ions into the flame 804. For example, emitting ions into the flame 804 may increase the surface area of the flame 804 to thereby decrease the temperature of the flame 804, which may affect one or more characteristics of the combustion-deposited film 808. For example, the ions emitted into the flame may be further directed by another counter electrode (not shown) that is biased oppositely to the charge of the ions to cause a so called “ionic wind.”

It should be noted that any of the embodiments shown in FIGS. 1-6 may be used in combination with the embodiments shown in FIGS. 7 and 8.

In an embodiment, a method of combustion flame deposition is disclosed. The method includes directing a flame output from a burner toward a substrate, and introducing at least one precursor into the flame, wherein the at least one precursor is a precursor for forming a combustion-deposited film on the substrate. The method further includes applying an electric field at least proximate to the flame to selectively influence a characteristic of combustion in the flame and/or deposition of a combustion-deposited film produced from the flame the flame, and combustion depositing the combustion-deposited film onto the substrate from the at least one precursor introduced to the flame.

In an embodiment, the substrate includes at least one of silica, a silicate, silicon, diamond, tungsten carbide, molybdenum, or glass. In an embodiment, the substrate includes a surface that is pre-seeded with particles such as, but not limited to, diamond particles, carbide particles, metal particles, metalloid particles, oxide particles, nitride particles, boride particles, or carbonate particles. In an embodiment, the method may include polishing a surface of the substrate onto which the combustion-deposited film is deposited before introducing the at least one precursor into the flame.

In an embodiment, the method may include supporting the substrate on a cooling/heating stage configured to control the temperature of the substrate. The method may further include cooling the substrate to a temperature of about 700° C. to about 1050° C., about 740° C. to about 900° C., or about 760° C. to about 780° C. In an embodiment, the method may further include cooling the substrate sufficiently to result in a generally smaller average deposition grain size of the film than an average deposition grain size of the film without cooling the substrate. Likewise, the method may further include cooling the substrate sufficiently to result in a generally larger average deposition grain size of the film than an average deposition grain size of the film without cooling the substrate.

In an embodiment, the method may further include selectively cooling the flame with an ionic wind generated from the at least one electrode adjacent to the flame. The ionic wind used to selectively cool the flame may, for example, be generated by the ionizing elements 720 and 816 discussed with respect to FIGS. 7 and 8.

In an embodiment, introducing the at least one precursor into the flame may include introducing at least one of silane, methane, tungsten hexafluoride, acetylene, oxygen or ethylene into the flame. Other precursors may include solutions injected into the flame, such as metal-salt solutions. For example, the metal-salt solutions may include silicon chloride, titanium chloride, tin chloride, or combinations thereof. Likewise, introducing at least one precursor into the flame may include introducing at least one precursor into the flame capable of forming at least one of a metal, an alloy, a metal oxide, a nitride, diamond, diamond-like carbon, a carbide, a fluoride, a boride, or a carbonate.

In an embodiment, an inner flame tip may be positioned at a distance of about 0.1 mm to about 2.0 mm or about 0.25 mm to about 0.75 mm from the substrate. In one embodiment, combustion depositing the film onto the substrate may include combustion depositing the film onto the substrate for a time period of about 60 minutes to about 120 minutes or about 80 minutes to about 100 minutes.

In an embodiment, combustion depositing the film includes growing crystals on a surface of the substrate, the crystals including at least one of at least one diamond crystal or at least one silicate crystal. In an embodiment, the method of combustion depositing may further include applying a negative voltage to the substrate sufficient to grow crystal facets substantially parallel to a surface of the substrate. For example, the method may include applying a negative voltage to the substrate of about −200 V to about −300 V relative to the flame.

In an embodiment, any of the combustion systems or methods described herein may be performed by a computer system having at least one processor configured to execute computer-executable instructions and process operational data. For example, the processor may be operably coupled to a memory storing an application including computer-executable instructions and operational data constituting a computer program to perform acts of a method and incorporated in a controller. In one example, the processor may be operably coupled to a memory storing an application including computer executable instructions and operational data constituting a program to control combustion characteristics of a flame. In another example, the processor may be operably coupled to a memory storing an application including computer executable instructions and operational data constituting a program to control a voltage source to, for example, generate a time-varying electrical field having a selected waveform.

The memory may be embodied as a computer readable medium, such as a random access memory (“RAM”), a hard disk drive, a static storage medium such as a compact disk, DVD, or other non-transitory storage medium. The memory may further store property data describing properties one or more of the flame, precursors, or electrode assemblies as described hereinabove. The computer system may further include a display coupled to the processor. The processor may be operable to display the images of the flame and other graphical illustrations of the characteristics of the flame on the display.

In some embodiments, the processor may also be operably coupled to and control operation of one or more voltage sources that apply a charge to one or more of the electrodes and/or the supply of at least one precursor. For example, the memory may have computer-executable instructions stored thereon for having the processor direct one or more voltage sources to apply a charge to the electrodes such that the one or more voltage sources and the electrodes collectively apply an electric field to one or more regions at least proximate to a flame and selectively introduce the at least one precursor into the flame. It will be appreciated that the computer systems described herein may include any suitable computer system including personal computers, desktop computers, laptop computers, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, PDAs, tablets, combinations thereof, or the like.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting. 

What is claimed is:
 1. A combustion deposition system, comprising: a burner configured to output a flame; at least one supply of at least one precursor in fluid communication with the burner such that the at least one precursor can be introduced to the flame, wherein the at least one precursor is for forming a combustion-deposited material by interacting with the flame; at least one electrode positioned at least proximate to the flame when the flame is output from the burner; and at least one voltage source operatively coupled to the at least one electrode; wherein the at least one electrode and the at least one voltage source are collectively configured to generate an electric field in one or more regions at least proximate to the flame effective to influence at least one characteristic of combustion of the at least one precursor in the flame and/or at least one characteristic of the combustion-deposited material.
 2. The combustion deposition system of claim 1 wherein the burner is the at least one electrode.
 3. The combustion deposition system of claim 1 wherein the burner acts as an additional electrode configured to cooperate with the at least one electrode to generate the electric field therebetween.
 4. The combustion deposition system of claim 1 wherein the electric field includes a time varying electric field.
 5. The combustion deposition system of claim 1 wherein the electric field includes a substantially constant electric field.
 6. The combustion deposition system of claim 1 wherein the at least one electrode includes a plurality of electrodes configured to apply the electric field to the one or more regions at least proximate to the flame.
 7. The combustion deposition system of claim 1, further comprising one or more ionizing elements positioned adjacent to the flame, the one or more ionizing elements configured to influence one or more characteristics of the flame.
 8. The combustion deposition system of claim 1, further comprising one or more ionizing elements positioned adjacent to the flame, the one or more ionizing elements configured to generate an ionic wind sufficient to affect a temperature of the flame.
 9. The combustion deposition system of claim 1 wherein the at least one electrode includes a plurality of electrodes arranged in a generally hollow configuration laterally surrounding the flame.
 10. The combustion deposition system of claim 9 wherein the generally hollow configuration is a generally hollow elliptical pattern, a generally hollow rectangular pattern, a generally hollow triangular pattern, a generally hexagonal pattern, or a generally polygonal pattern.
 11. The combustion deposition system of claim 1 wherein: the flame includes an inner flame having a shape; and the at least one electrode and the at least one voltage source are collectively configured to influence the shape of the inner flame by varying the application of the electric field.
 12. The combustion deposition system of claim 1 wherein the at least one electrode and the at least one voltage source are collectively configured to influence one or more kinetic properties of one or more chemical reactions within the flame.
 13. The combustion deposition system of claim 1 wherein the at least one electrode and the at least one voltage source are collectively configured to influence at least one of a stoichiometry of one or more chemical reactions within the flame, crystal structure of the combustion-deposited material, or phase size of the combustion-deposited material.
 14. The combustion deposition system of claim 1 wherein the at least one electrode and the at least one voltage source are collectively configured to influence distribution of chemical species of the flame by varying application of the electric field at selected locations and/or times.
 15. The combustion deposition system of claim 1 wherein the at least one electrode and the at least one voltage source are collectively configured to influence one or more combustion characteristics of the flame by varying a voltage applied by the at least one voltage source at selected locations and/or times.
 16. The combustion deposition system of claim 1, further comprising a substrate positioned adjacent to the flame for receiving the combustion-deposited material thereon.
 17. The combustion deposition system of claim 1 wherein the at least one supply of the at least one precursor includes at least one precursor for forming at least one of a metal, an alloy, a metal oxide, a nitride, diamond, diamond-like carbon, a carbide, a fluoride, a boride, a carbonate, or a nanoparticle combustion-deposited material.
 18. The combustion deposition system of claim 1 wherein the at least one supply of the at least one precursor includes at least one of ethylene, oxygen, acetylene, methane, tungsten hexafluoride, silane, or a metal-salt solution.
 19. The combustion deposition system of claim 1, further comprising a cooling stage configured to cool a temperature of a substrate positioned thereon on which the combustion-deposited material can be deposited.
 20. The combustion deposition system of claim 19 wherein the cooling stage is configured to cool the substrate to about 700° C. to about 850° C.
 21. The combustion deposition system of claim 19 wherein the cooling stage is configured to cool the substrate to about 740° C. to about 800° C.
 22. The combustion deposition system of claim 19 wherein the cooling stage is configured to cool the substrate to about 760° C. to about 780° C.
 23. The combustion deposition system of claim 1 wherein the nozzle includes a passageway in fluid communication with the at least one supply of the at least one precursor through which the at least one precursor can be introduced to the flame.
 24. The combustion deposition system of claim 1 wherein the at least one supply of the at least one precursor is configured to introduce the at least one precursor adjacent to the nozzle and into the flame.
 25. A method of combustion flame deposition, comprising: directing a flame output from a burner toward a substrate; introducing at least one precursor into the flame, wherein the at least one precursor is for forming a combustion-deposited material on the substrate by interacting with the flame; applying an electric field at least proximate to the flame to selectively influence at least one characteristic of combustion in the flame and/or at least one characteristic of the combustion-deposited material produced from the flame; and combustion depositing the combustion-deposited material onto the substrate from the at least one precursor introduced to the flame.
 26. The method of combustion flame deposition of claim 25 wherein the substrate includes at least one of silica, a silicate, silicon, diamond, tungsten carbide, molybdenum, or glass.
 27. The method of combustion flame deposition of claim 25 wherein the substrate includes a surface that is pre-seeded with particles.
 28. The method of combustion flame deposition of claim 25 wherein the substrate includes a surface that is pre-seeded with at least one of diamond particles, carbide particles, metal particles, metalloid particles, oxide particles, nitride particles, boride particles, or carbonate particles.
 29. The method of combustion flame deposition of claim 25, further comprising polishing a surface of the substrate before introducing the at least one precursor into the flame.
 30. The method of combustion flame deposition of claim 25, further comprising cooling the substrate to a temperature of about 700° C. to about 1050° C.
 31. The method of combustion flame deposition of claim 25, further comprising cooling the substrate to a temperature of about 740° C. to about 900° C.
 32. The method of combustion flame deposition of claim 25, further comprising cooling the substrate to a temperature of about 760° C. to about 780° C.
 33. The method of combustion flame deposition of claim 25, further comprising cooling the substrate sufficiently to result in a generally smaller average deposition grain size of the combustion-deposited material than an average deposition grain size of the combustion-deposited material without cooling the substrate.
 34. The method of combustion flame deposition of claim 25, further comprising cooling the substrate sufficiently to result in a generally larger average deposition grain size of the combustion-deposited material than an average deposition grain size of the material without cooling the substrate.
 35. The method of combustion flame deposition of claim 25, further comprising selectively cooling the flame with an ionic wind generated from the at least one electrode adjacent to the flame.
 36. The method of combustion flame deposition of claim 25 wherein applying the electric field includes applying the electric field via one or more electrodes.
 37. The method of combustion flame deposition of claim 25 wherein applying the electric field includes applying a time-varying electric field.
 38. The method of combustion flame deposition of claim 25 wherein applying the electric field includes applying a substantially constant electric field.
 39. The method of combustion flame deposition of claim 25 wherein applying the electric field includes varying the application of the electric field to control one or more combustion characteristics of the flame.
 40. The method of combustion flame deposition of claim 25 wherein applying the electric field includes varying a magnitude of a voltage applied by at least one or more voltage sources.
 41. The method of combustion flame deposition of claim 25 wherein applying the electric field includes varying the application of the electric field at selected locations and/or times.
 42. The method of combustion flame deposition of claim 25 wherein introducing at least one precursor into the flame includes introducing into the flame at least one of silane, methane, tungsten hexafluoride, acetylene, oxygen, ethylene, or a metal-salt solution.
 43. The method of combustion flame deposition of claim 25 wherein introducing at least one precursor into the flame includes introducing into the flame at least one precursor for forming at least one of a metal, a metal oxide, a nitride, diamond, diamond-like carbon, a carbide, a fluoride, a boride, or a carbonate.
 44. The method of combustion flame deposition of claim 25, further comprising positioning an inner flame tip at a distance of about 0.1 mm to about 2.0 mm from the substrate.
 45. The method of combustion flame deposition of claim 25, further comprising positioning an inner flame tip at a distance of about 0.25 mm to about 0.75 mm from the substrate.
 46. The method of combustion flame deposition of claim 25 wherein the combustion-deposited material is configured as a film or discrete particles.
 47. A method of combustion flame deposition, comprising: directing a flame output from a burner toward a substrate; introducing at least one precursor into the flame for forming a combustion-deposited material on the substrate by interacting with the flame, wherein the at least one precursor includes at least one of silane, methane, tungsten hexafluoride, acetylene, oxygen, ethylene, or a metal-salt solution; applying an electric field at least proximate to the flame to selectively influence at least one characteristic of combustion in the flame and/or at least one characteristic of the combustion-deposited material produced from the flame; and combustion depositing the combustion-deposited material onto the substrate from the at least one precursor introduced to the flame, wherein the combustion-deposited material is configured as a film or discrete particles. 